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AC POWER CONSIDERATIONS
Be sure the SRM150 is plugged into an outlet that is
able to supply enough current for the amplifier.
Under maximum SPL conditions, where musical peaks
are just hitting the limiter, the SRM150 model draws 2
amps on average. Under normal conditions, the current
draw is below 1 amp.
We recommend that a stiff (robust) supply of AC
power be used because the amplifier places high cur-
rent demands on the AC line. The more power that is
available on the line, the louder the speaker will play
and the more peak output power will be available for
cleaner, punchier bass. A suspected problem of “poor
bass performance” is often caused by a weak AC supply
to the amplifier.
If lighting is used in a show, it is preferable to power
the lights from a separate AC circuit than the one
powering the audio equipment. This will help minimize
noise from the lights coupling into the audio (particu-
larly if SCRs, or light-dimmer switches, are used).
Wherever possible, connect all of your audio equip-
ment to the same electrical circuit. This will help
reduce the possibility of a ground loop problem causing
an annoying hum in your speakers.
A maximum of five SRM150s can be connected per
15A service (120 VAC). This allows each SRM150 to be
safely operated at its maximum level.
When turning your system on, turn on the SRM150s
last. This will stop any turn-on thumps and bangs from
your source equipment being amplified.
When turning off your system, turn off the SRM150s
first. This will prevent any turn-off thumps and bangs
from your source equipment being amplified.
When setting up for a show, often
you are plugging into an AC power
distribution system you know nothing
about. You may even be faced with 2-
wire outlets that are missing the third
safety ground pin. It’s a good idea to have a three-wire AC
outlet tester in your toolbox so you can check the outlets
yourself to make sure they are wired correctly. These
testers will tell you if the polarity of the hot and neutral
wires is reversed and if the safety ground is disconnected.
Don’t use an outlet if it is wired im-
properly! This is to protect yourself
as well as your equipment.
Never remove the ground pin on the
power cord of the SRM150 or any other
component. This is very dangerous.
CARE AND MAINTENANCE
Your Mackie active loudspeaker will provide many
years of reliable service if you follow these guidelines:
Avoid exposing the loudspeaker to
moisture. If it is set up outdoors, be
sure it is under cover if you expect rain
or you live in Washington.
• Avoid exposure to extreme cold (below freezing
temperatures). If you must operate the loudspeaker
in a cold environment, warm up the voice coil slowly
by sending a low-level signal through it for about 15
minutes prior to high-power operation.
• Use a slighty damp cloth with a mild soap solution
to clean the cabinet. Only do this when the power
is turned off. Avoid getting moisture into any of the
openings of the cabinet, particularly where the driver is
located.
